Cigarette paper is one of effective ways for achieving harm reduction and tar reduction for cigarettes. Cigarette paper consists of three parts: plant fibers, inorganic fillers and additives, wherein the additives, especially combustion additives, can affect combustion performance of cigarettes and improve combustion quality of cigarettes through changing the combustion state of cigarette paper, thus affecting smoke components and smoke amount of cigarettes. Application of the cigarette paper additive is an important means of imparting high value added to the cigarette paper and highlighting functionalities of the cigarette paper, and research and development of the functional cigarette paper additive are important technical means of imparting high technical content to the cigarette paper, thus adapting to requirements of safety and low harm for cigarettes.
Organic alkali metal salt is a combustion additive for increasing the static combustion rate of the cigarette paper and cigarettes. (Liu C et. al., Beitrage zur Tabakforschuang International/Contributions to Tobacco Research, 2003, 20(5):341-347) sprayed potassium malate, potassium citrate and potassium tartrate onto tobacco shreds, and found that the suction temperature almost had a linear decrease when total potassium content of the potassium malate added is 3.1%-8.3%, meanwhile the draw resistance increase gradually. When total potassium content in the tobacco shreds is 5.1%, potassium salts of three organic acids can reduce nicotine by 25%-32% and reduce CO by 24%˜35% in the mainstream smoke. (Yamamoto T et. al., Beitrage zur Tabakforschuang International, 1990, 14(6):379-385) investigated effects of addition of potassium salts on reduction of tar, nicotine and CO in the mainstream smoke, and found that the delivery amount of tar, nicotine and CO decreases as the amount of potassium salts added to the tobacco shreds increases. If malate is added, the puff number almost has no change, and if nitrate is added, the puff number slightly decreases. For CO reduction, the potassium malate is more effective than potassium nitrate, and for nicotine, it is the opposite. Both addition of potassium salts and increase in the amount of potassium salts can affect CO delivery amount through decreasing peak temperature of combustion areas. Addition of potassium malate less than 2% can eliminate irritability of smoke and flavour loss. (Da Ya et. al., Tobacco Science & Technology, 1998 (1):11-12 ; 1998 (5):3-4) investigated effects of some potassium salts on combustibility and tar release of cigarettes, indicating that addition of a proper amount of potassium salts can accelerate cigarette combustion.
U.S. Pat. Nos. 5,248,396, 5,364,964, 5,591,893 and US20040035715 respectively introduced several different methods for preparing butane tetracarboxylic acid. Patent No. US20010018542 disclosed a method for preparing butane tetracarboxylic acid and applications thereof in treating cellulose fibers, woven fabrics and paper products. The butane tetracarboxylic acid is cross-linked with the amorphous region of cellulose by reacting with a hydroxy group on the cellulose, this treatment manner without crimple and without ionization ensures that the fabric could keep original shape when it is washed and rubbed, and cotton, flax, rayon, paper and the like can be treated by butane tetracarboxylic acid. Application of the butane tetracarboxylic acid in combustion additive of the cigarette paper has not been reported.
Common combustion additives of the cigarette paper include citrate, malate, tartrate, succinate, acetate, etc. Now, combustion additive used by most of cigarette paper manufacturing enterprises in China is the mixed salt of potassium citrate and sodium citrate. Though use of the citrate can increase static combustion rate and reduce the puff number, however, CO delivery amount of each puff increases greatly, so excessive use of citrate can also have negative effects on sensory quality of cigarettes. With overall consideration, it is preferable to use a new cigarette paper additive which has effects of harm reduction and tar reduction, also has no significant negative effects on cigarette flavor, and meets food safety requirements, which becomes a new topic in the field of preparation technology of cigarette materials.